This case report describes an incidentally discovered right atrial mass, partially seen on abdominal and pelvic CT during workup for cholecystitis, that arose from the crista terminalis and was confirmed as a myxoma at pathology, highlighting an atypical origin and location of a common cardiac tumor.
A right atrial mass was incidentally detected on CT of the abdomen and pelvis performed for workup of cholecystitis.
Multimodality imaging showed that the right atrial mass arose from the crista terminalis.
Pathologic examination confirmed that the right atrial mass was a myxoma.
Cardiac myxomas are the second most common benign cardiac tumor in adults and usually arise from the interatrial septum in the left atrium.
This case report describes a patient who had a CT scan of the abdomen and pelvis because of suspected gallbladder inflammation (cholecystitis). The scan happened to catch part of a mass in the heart's right upper chamber (the right atrium). Further imaging with ultrasound, MRI, and CT angiography showed that the mass was attached to a ridge of tissue in the right atrium called the crista terminalis. Examination of the tissue confirmed it was a myxoma, a noncancerous heart tumor. Most heart myxomas grow in the left upper chamber, attached to the wall between the two upper chambers, and are usually found because they cause heart-related symptoms or blockages from tumor fragments. This case shows that a myxoma can occur in an unusual place and can be found by chance on scans done for another reason. This research suggests that radiologists reviewing abdominal imaging may sometimes see parts of the heart and should be aware that unexpected findings there could be a myxoma. As a single case report, it cannot show how often this happens.
Frisby K, Malecki K, Larsson L, Mansour J. (2026). Multimodality Imaging and Pathology of an Incidentally Discovered Right Atrial Myxoma Arising from the Crista Terminalis.. Radiology. Cardiothoracic imaging. https://doi.org/10.1148/ryct.260181